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It’s a carnivore’s worst nightmare: A virus is sweeping through America’s hog farms, causing massive die-offs among piglets. Pork prices have spiked, rising 14 percent in the past year, due in large part to the 7 million casualties from the Porcine Epidemic Diarrhea virus (PEDv). With bacon retailing at $6.11 per pound in American cities, farmers and food lovers alike have begun to wonder if this could be the end of bacon.

The aporkalypse began last spring, when piglets on farms in Iowa began dying of severe diarrhea. At first, officials believed it was caused by the transmissible gastroenteritis virus, which has been known to cause significant outbreaks on U.S. farms. But measures to contain this virus weren’t working, and the U.S. Department of Agriculture began to look more closely. They found PEDv.

It’s alarming, says X.J. Meng, a virologist at the Virginia-Maryland College of Veterinary Medicine, because PEDv had never been seen in the U.S. before. “It’s not a new virus-it’s been around since the 1970s, but it’s new to the U.S.,” Meng said. “The Iowa and Minnesota strains are nearly identical to the Chinese [PEDv] virus,” Meng explains.

Because of the initial attribution to a more mundane pathogen, scientists have been unable to track down exactly how the virus may have first arrived in this country. What’s happened since then, however, has been much easier to follow. In one year, PEDv has spread to more than 30 states, even during times when viruses similar to PEDv aren’t readily transmitted. Since no pigs are immune to PEDv, the virus has spread quickly, with high death rates in its path.

The USDA only required farmers to report the presence of PEDv in their herds this past June, more than a year after the virus first entered the U.S. This makes case counts a little fuzzy, but most researchers estimate that 100,000 pigs and piglets are dying from PEDv each week. Since the outbreak began, more than 7 million have died. The 5 percent drop in the U.S. hog herd from 2013 to 2014 (from 65.2 million pigs to 62.1 million) is nearly all attributable to PEDv. These declines have led to spikes in pork prices as well.

Although PEDv might not have a name that sends shivers up the spine quite like “Ebola” or “Marburg,” it has torn through the pig population like many scarier-sounding viruses do in humans. As its name suggests, PEDv causes serious diarrhea. It sounds like a fairly banal symptom-none of the bleeding out of every orifice and then some that physicians are seeing in the current Ebola outbreak. But diarrhea can and does kill in both humans and pigs. Older pigs may be sick for a few days, but they generally survive. Piglets, especially those under 10 days of age, aren’t so lucky. Without the reserves of their older cousins, piglets often don’t survive PEDv infections. Like many gastrointestinal viruses, PEDv is spread by the fecal-oral route, and it can also survive for long periods of time on inanimate objects and solid surfaces.   

This last capability of the virus appears to be how the pathogen is spreading between farms in different states. Say a sick pig is loaded onto a transport vehicle, says Jim McGraw, Wisconsin’s state veterinarian. It can not only spread the virus to other pigs on that truck, but viable virus particles can remain on the truck when the next batch of pigs arrives. Then, those pigs go to their various destinations, taking the virus with them. “We haven’t yet identified every means of spread,” McGraw says.

To stop the spread of virus, farmers have had to become experts in biosecurity. Between runs, transport trucks not only must be cleaned, they now have to be sanitized. Any vehicles that arrive on a farmer’s property are hosed down with disinfectant. Feed origins are scrutinized. Farmers have begun limiting access to their farms and pigs to prevent virus importation. Anyone having contact with the animals must wear disposable suits and booties to prevent the spread of infections. A visit to your local pig farm now requires nearly as much preparation and gear as entering a CDC biocontainment zone.